The present invention relates to a method of, and apparatus for, focussing and steering charged particle beams (e.g. beams of ions or beams of electrons) and for shaping such beams into a range of desired configurations.
Generally, the devices of the prior art currently in use to focus electrons, that is, to cause electrons to converge toward a common point or focus, all employ a cathode for emitting electrons and an anode to which is applied a voltage for accelerating the electrons from the cathode to the anode and use either or both magnetic or electrostatic fields disposed between the anode and the cathode to deflect the electrons and cause them to converge to a common point, for example, the devices used to focus electrons in a cathode ray tube or electron microscope. However, such devices are limited in their ability to reach the high beam currents that are required in high energy physics devices.
In the field of synchrotron radiation the devices employed in the prior art, e.g., synchrotrons are enormously expensive and hence their use is restricted.